@lalitk , what you say makes a lot of sense, as the rack impacts every component at once. In fact, by far the biggest boost was when I installed four of Herbie’s “Giant Fat Dots” under my current heavy wooden shelf. There was a sudden boost that was far larger than when installing Herbie’s Tenderfeet under each individual component, as it improved all components at once.
However - I first installed the Giant Fat Dots under my shelf, I didn’t do it right. I let the shelf’s four plastic feet rest on the Fat Dots. Herbie’s says these are only for applications where you are interfacing two broad, flat surfaces. When I corrected this fairly recently and moved the fat dots to another location under the shelf away from the shelf’s feet (which raises the shelf’s feet off the floor as the Fat Dots are taller than the shelf’s feet), I couldn’t believe how much stability and solidity was added to the image. Prior to correcting this, the image was always every so slightly “skewing” in one direction or another, especially after I moved a component on my shelf which I guess slightly changed how the shelf’s feet were digging into the fat dots. The curse of a revealing system.
I expect a high end audio rack would go even farther as you say. The trouble is for me, most tend to look more like science equipment than a welcoming presentation of your system, at least from what I’ve seen.
I’ve just ordered from Herbie’s those discs that you rest on top of your gear. I did this after I experimented by placing a small square piece of granite on top of each component in my system and realizing that it helps. Not to the degree that the Tenderfeet help but still a boost. Unfortunately you can’t really do this with the MU1 because of its chassis design and the big button wheel on top (there I made this at least a bit on-topic :) ). I was able to do it with the Tambaqui despite its curved top. For all components I found the sound became a bit more crisp and sweet in the upper mids and up top.